Japanese Patent Laid-open No. Hei7-230062 is known as a new type rimless spectacles. The rimless spectacles have pairs of lug portions on a bridge for joining the right and left spectacle lenses and on an end piece for joining a temple to a spectacle lens, and pairs of closed-end holes, extending inside a lens, in edged faces of the spectacle lenses in correspondence to the positions of the bridge and the end piece. The spectacle lens is joined to the bridge and the end piece by inserting a pair of the lug portions into the closed-end holes and bonding with adhesive. According to the above description of rimless spectacles, compared to conventional rimless spectacles generally called a two-point type or a three-piece type, a screw piercing from the front face of a lens to the back face in the vicinity of an end of the lens is omitted, therefore obtaining the advantage of an expansion of the effective range of vision and the like.
Conventionally, to drill a closed-end hole in an edged face of a spectacle lens to extend inside the lens, after a guide member shaped as a small part which is provided with a pair of guide holes which guide a drill as a drilling instrument of a drill press, is attached on an edged face of a lens with a double-sided adhesive tape, a technician holds the spectacle lens with his/her hand, and then inserts the drills into the respective guide holes of the guide member in sequence, to form the closed-end holes on the edged face of the lens with the guiding action of the guide hole.
However, the drilling process of the closed-end hole is carried out while the technician is holding the spectacle lens with his/her hand, so that the holding of the spectacle lens is not stable, and naturally, the spectacle lens is not stable with respect to the drill, thus experience is required to drill the closed-end hole with accuracy. Since the number of spectacle lenses in which the closed-end holes can be formed in a fixed hour period is limited, there is the disadvantage of the increase in production cost. Additionally, the spectacle lens and, the bridge and the end-piece as components of spectacle frames which have lug portions in pairs easily have a manufacture error or a finishing error. Therefore, the drilling operation for the spectacle lens has to be carried out while taking such errors into account, so that a lot of time, experience and skill are required for the drilling operation.
It is an object of the present invention to provide a drilling jig for a spectacle lens which is capable of drilling a closed-end hole in an edged face of the spectacle lens with accuracy without experience, and increasing the number of spectacle lenses in which the closed-end holes are formed in a fixed time period.
It is another object of the present invention to provide a jig for effortlessly manufacturing the drilling jig.
It is still another object of the present invention to provide a method of drilling a spectacle lens which is capable of performing the precise drilling operation with respect to rimless spectacles of which closed-end holes are formed in the edged faces of the lenses for insertion of the holding members of spectacle-frames, and the resulting spectacle lens.